The present invention relates to endless tracks to be used with tracked vehicles. In particular, the invention relates to improved endless tracks to be used with tracked vehicle wherein said track comprises evacuation means for allowing accumulated debris to be expelled from said track.
Tracked vehicles are well known and have been in existence for a number of years. Tracked vehicles are, for example, in use in a variety of fields, whether as earth moving equipment, such as bulldozers, mechanical excavators, etc., farming equipment, military equipment, or vehicles used in any number of specialized fields, such as for fighting fires, for bomb disposal, remote manipulation, etc. Tracked vehicle may also be used as snow cleaning equipment, or as ski hill grooming equipment.
The used of tracked vehicles, in particular, the use of tracked vehicles on hard or rocky ground comprises the disadvantage that the tracks may, sooner or later, become clogged or filled up with debris such as stones, rocks, branches, earth, etc. This debris may, through time, cause the tracks to become jammed and the vehicle to stop. Further, even if a vehicle is not brought to a standstill by debris, its efficiency may be reduced, resulting in an increase in power consumption and a reduction of the speed or pulling power of the vehicle. Finally, the accumulation of rocks, debris, etc. may cause premature wear and tear of the track and its constituent parts, and may eventually cause the premature breakdown of the tracked vehicle, or the track itself, the wheels, gears, suspension mechanisms and other mechanisms commonly used with such tracked vehicles. The accumulation of debris may therefore increase maintenance and replacement costs of known tracked vehicles.
Tracks and tracked vehicles are well known in the art, as exemplified by U.S. Pat. No. 5,363,936 to Grawey et al., U.S. Pat. No. 2,385,758 to Hansen, U.S. Pat. No. 1,808,446 to Armington, U.S. Pat. No. 1,924,161 to Knox, U.S. Pat. No. 1,901,421 to Streich, U.S. Pat. No. 2,167,039 to Ekbom, U.S. Pat. No. 3,378,314 to Knowles, and U.S. Pat. No. 2,314,355 to Knox. The prior art discloses tracks which, without being the object of the patent, are provided with holes and openings which may, in a haphazard manner, allow for the exit therethrough of debris, snow etc. such for as example Hansen, wherein an open center snow track is disclosed. However this open ended snow track may allow as much or more debris and snow to be introduced into the track, as may be evacuated, and further lacks the lateral rigidity and sturdiness and necessary for heavy duty use. Further Streich discloses links which include curved portions which serve to physically push and clear the track of dirt, however such curved portions are disposed on the outside of the track, and therefore serve the purpose of clearing any dirt or accumulated debris which may be found on the outside of the track, and is of no use to clear the debris which may find its way inside the track, i.e. between the wheels. Also, Ekbom provides for an offset or staggered arrangements of driving lugs, however the arrangement of the lugs is such that the space between adjacent lugs becomes constricted as the track is wound-about the end wheels of the vehicle, therefore restricting the manner in which dirt and/or debris can be evacuated.
Further, each of the above disclosed prior art comprise cleat members or lugs which keep the track aligned with the wheels, and which cleat members are shaped and configured such that the space between adjacent cleat members are widest at the point where they come into contact with the track, and then they become narrower the further away they are from the track. As may be seen, the broadest or widest aspect of the cleat is therefore disposed immediately adjacent the track, and the narrowest part of the cleat is disposed away from the track. The effect of this arrangement or geometry is to cause any opening which may be present between adjacent cleats to be narrowed or closed off as the track is wound about the end or traction wheels. Thus, the prior art discloses tracks and track arrangements wherein the opening between adjacent cleats are constricted or closed off, precisely at the point where debris may, through the force of gravity, be looking for an exit from the track, namely when the tracks go around the end wheels. Thus, the configuration and disposition of the cleats in the prior art hamper, or even preclude the evacuation of debris from the track.
Further, the above cited prior art do not actually provide for an opening, or tunnel or evacuation means which may allow the evacuation or expelling of accumulated debris found therein, at all times, and in all positions of the track.
It would be therefore advantageous to provide for a track configured and disposed such that evacuation means are provided which would allow for the expelling at all times of dirt and/or debris which may have accumulated in the tracks.
It would be further advantageous to provide for a track comprising paddles which are configured and disposed such that an opening is disposed between adjacent paddles, such that the cross-sectional area of this opening may remain substantially constant as the track moves about the driving wheels.
It would be further advantageous to provide for a track comprising paddles whose geometry is such that even when the paddle come closer in contact with one another, an evacuation opening, i.e. tunnel, or evacuation means, adjacent the track remains open and of substantially constant cross-sectional area at all times.
It would be further advantageous to provide for a track comprising paddles whose geometry make it such that the track is a self-cleaning track.